Immersive visual systems are widely used in simulation applications to create out of the window images for pilots or drivers or to create visually surrounding virtual images for one or multiple users.
Currently, there are four main techniques to create large field of view immersive visual display systems.
The first known technique to generate an immersive visual display system with a large field of view is by projecting, with a plurality of projectors, on the front of a spherical surface. The advantage of front projected systems is that they have a compact footprint but their projector placement is complex and widescreen projectors are used in a less optimal way resulting in systems with a lower resolution. Pilots viewing from inside the spherical surface experience very good ergonomics as the distance between the pilot's eyes and the screen is almost constant, independent of the angle at which the pilot looks at the screen.
The second technique consists in projecting onto a rear projected spherical surface with multiple projectors. The advantage of rear projected spherical displays is the fact that the projectors are positioned around the rear projected screens and therefore illuminate the screen in a more uniform way resulting in a display that has a more uniform and higher resolution. Widescreen projectors with aspect ratios of more than 1.34 typically cannot be matched very optimally with a spherical screen resulting in a lot of loss of pixels and brightness. The projectors can be hard edged or soft-edged on the screen surface. Pilots inside the spherical surface get very good ergonomics as the distance between the pilot's eyes and the screen is almost constant, independently of the angle at which the pilot looks at the screen.
The third way is by projecting on faceted displays, as described for example in U.S. Pat. No. 5,179,440 which describes a rear projection facetted dome. The system screen is then made up by a number of flat or moderately curved facetted rear projected screens with a projector behind each screen facet. The advantage of this approach is that the projector resolution can be very well used to optimize the screen resolution, even with widescreen projectors and that the footprint can be kept small. The drawback is the visual ergonomics for the pilots are strongly compromised as the distance between the pilot's eyes and the screen is no longer constant, changes in a non-constant way at the facet edges and is dependent of the angle at which the pilot looks at the screen.
The fourth technique is a combination of the second and third techniques, i.e. by creating a hybrid rear projected solution that is a partly rear projected continuous surface and faceted surface. Again here, the wide screen projectors can be used efficiently and the footprint can be kept compact but the visual ergonomics for the pilots are strongly compromised for the same reasons as the faceted display.
U.S. Pat. No. 5,023,725 describes a method and an apparatus for dodecahedral imaging system. U.S. Pat. No. 9,188,850 provides a Display System for high Definition projectors. WO2012/040797 discloses a Curved Back projection Screen. US20120218170 discloses a Method and Apparatus for a Wide Field of View Display, US2007/0009862 provides a Simulator using a non-spherical projection surface and U.S. Pat. No. 9,110,358 proposes a method for creating and a system for a constant vertical resolution toroidal display.